Dubious eBay SD Cards – Caveat Emptor

Over the years, I have purchased a number of SD cards through eBay – often shipped directly from China. Today I was reading the setup instructions for a recent acquisition – a PINE-64 board. Pine-64 was adamant that the micro-SD card used be over 8GB and of Class 10. I dug around on the shelf and came up with a spare 32GB micro-SD. It was marked as Class-4. No good for this application BUT I got to wondering how it would test. A photo of the SD card’s markins is below, front and back.

I had recently discovered a suite of SD testing tools called F3 by Michel Machado. I downloaded the source and compiled the suite. Next, I ran the tools against the SD card. The results were BAD! The card is a fake and only has 7GB usable. The console’s output is pasted below. The reported average writing speed is 3.07 MB/s, which would be between a Class 2 and Class 4. The card is marked Class 4 so the speed is also a fake. I’ve learned my lesson – no more direct-from-China SD cards unless I can truly trust the seller – which seems pretty difficult on eBay. Consequentially, I think that I will stick to companies with good return policies (Amazon, NewEgg and Wal-Mart) and immediately test the new card with F3. Caveat Emptor!

dzrmo@bergamont ~/src/f3-6.0 $ ./f3write /media/dzrmo/9C6F-1ECD
Free space: 29.80 GB
Creating file 1.h2w ... OK!
Creating file 2.h2w ... OK!
Creating file 3.h2w ... OK!
Creating file 4.h2w ... OK!
Creating file 5.h2w ... OK!
Creating file 6.h2w ... OK!
Creating file 7.h2w ... OK!
Creating file 8.h2w ... OK!
Creating file 9.h2w ... OK!
Creating file 10.h2w ... OK!
Creating file 11.h2w ... OK!
Creating file 12.h2w ... OK!
Creating file 13.h2w ... OK!
Creating file 14.h2w ... OK!
Creating file 15.h2w ... OK!
Creating file 16.h2w ... OK!
Creating file 17.h2w ... OK!
Creating file 18.h2w ... OK!
Creating file 19.h2w ... OK!
Creating file 20.h2w ... OK!
Creating file 21.h2w ... OK!
Creating file 22.h2w ... OK!
Creating file 23.h2w ... OK!
Creating file 24.h2w ... OK!
Creating file 25.h2w ... OK!
Creating file 26.h2w ... OK!
Creating file 27.h2w ... OK!
Creating file 28.h2w ... OK!
Creating file 29.h2w ... OK!
Creating file 30.h2w ... OK!
Free space: 0.00 Byte
Average writing speed: 3.07 MB/s
dzrmo@bergamont ~/src/f3-6.0 $ 

dzrmo@bergamont ~/src/f3-6.0 $ ./f3read /media/dzrmo/9C6F-1ECD
                  SECTORS      ok/corrupted/changed/overwritten
Validating file 1.h2w ... 2097152/        0/      0/      0
Validating file 2.h2w ... 2097152/        0/      0/      0
Validating file 3.h2w ... 2097140/        0/     12/      0
Validating file 4.h2w ... 2097151/        0/      1/      0
Validating file 5.h2w ... 2097152/        0/      0/      0
Validating file 6.h2w ... 2097152/        0/      0/      0
Validating file 7.h2w ... 2097152/        0/      0/      0
Validating file 8.h2w ...  678512/        8/      0/1418632
Validating file 9.h2w ...       0/        0/      0/2097152
Validating file 10.h2w ...       0/        0/      0/2097152
Validating file 11.h2w ...       0/        0/      0/2097152
Validating file 12.h2w ...       0/        0/      0/2097152
Validating file 13.h2w ...       0/        0/      0/2097152
Validating file 14.h2w ...       0/        0/      0/2097152
Validating file 15.h2w ...       0/        0/      0/2097152
Validating file 16.h2w ...       0/        0/      0/2097152
Validating file 17.h2w ...       0/        0/      0/2097152
Validating file 18.h2w ...       0/        0/      0/2097152
Validating file 19.h2w ...       0/        0/      0/2097152
Validating file 20.h2w ...       0/        0/      0/2097152
Validating file 21.h2w ...       0/        0/      0/2097152
Validating file 22.h2w ...       0/        0/      0/2097152
Validating file 23.h2w ...       0/        0/      0/2097152
Validating file 24.h2w ...       0/        0/      0/2097152
Validating file 25.h2w ...       0/        0/      0/2097152
Validating file 26.h2w ...       0/        0/      0/2097152
Validating file 27.h2w ...       0/        0/      0/2097152
Validating file 28.h2w ...       0/        0/      0/2097152
Validating file 29.h2w ...       0/        0/      0/2097152
Validating file 30.h2w ...    8256/        0/      0/1661312

  Data OK: 7.33 GB (15366819 sectors)
Data LOST: 22.47 GB (47120157 sectors)
	       Corrupted: 4.00 KB (8 sectors)
	Slightly changed: 6.50 KB (13 sectors)
	     Overwritten: 22.47 GB (47120136 sectors)
Average reading speed: 13.77 MB/s

dzrmo@bergamont ~/src/f3-6.0 $ sudo ./f3probe --destructive --time-ops /dev/sdf
[sudo] password for dzrmo:
F3 probe 6.0
Copyright (C) 2010 Digirati Internet LTDA.
This is free software; see the source for copying conditions.

WARNING: Probing normally takes from a few seconds to 15 minutes, but
         it can take longer. Please be patient.

Bad news: The device `/dev/sdf' is a counterfeit of type limbo

You can "fix" this device using the following command:
f3fix --last-sec=15466495 /dev/sdf

Device geometry:
	         *Usable* size: 7.38 GB (15466496 blocks)
	        Announced size: 30.00 GB (62914560 blocks)
	                Module: 32.00 GB (2^35 Bytes)
	Approximate cache size: 3.88 MB (7952 blocks), need-reset=yes
	   Physical block size: 512.00 Byte (2^9 Bytes)

Probe time: 2'15"
 Operation: total time / count = avg time
      Read: 1.39s / 32937 = 42us
     Write: 2'09" / 125776 = 1.0ms
     Reset: 4.05s / 16 = 253.2ms
dzrmo@bergamont ~/src/f3-6.0 $ 

dzrmo@bergamont ~/src/f3-6.0 $ sudo ./f3fix --last-sec=15466495 /dev/sdf
F3 fix 6.0
Copyright (C) 2010 Digirati Internet LTDA.
This is free software; see the source for copying conditions.

Drive `/dev/sdf' was successfully fixed
dzrmo@bergamont ~/src/f3-6.0 $ 

dzrmo@bergamont ~/src/f3-6.0 $ sudo ./f3probe --destructive --time-ops /dev/sdf
F3 probe 6.0
Copyright (C) 2010 Digirati Internet LTDA.
This is free software; see the source for copying conditions.

WARNING: Probing normally takes from a few seconds to 15 minutes, but
         it can take longer. Please be patient.

Bad news: The device `/dev/sdf' is a counterfeit of type limbo

You can "fix" this device using the following command:
f3fix --last-sec=15466495 /dev/sdf

Device geometry:
	         *Usable* size: 7.38 GB (15466496 blocks)
	        Announced size: 30.00 GB (62914560 blocks)
	                Module: 32.00 GB (2^35 Bytes)
	Approximate cache size: 7.00 MB (14336 blocks), need-reset=no
	   Physical block size: 512.00 Byte (2^9 Bytes)

Probe time: 2'30"
 Operation: total time / count = avg time
      Read: 1.40s / 32937 = 42us
     Write: 2'28" / 215152 = 690us
     Reset: 494.2ms / 2 = 247.1ms
dzrmo@bergamont ~/src/f3-6.0 $ 

[[[ Ran gparted and reformatted the drive ]]

dzrmo@bergamont ~/src/f3-6.0 $ sudo ./f3probe --destructive --time-ops /dev/sdf
F3 probe 6.0
Copyright (C) 2010 Digirati Internet LTDA.
This is free software; see the source for copying conditions.

WARNING: Probing normally takes from a few seconds to 15 minutes, but
         it can take longer. Please be patient.

Bad news: The device `/dev/sdf' is a counterfeit of type limbo

You can "fix" this device using the following command:
f3fix --last-sec=15466495 /dev/sdf

Device geometry:
	         *Usable* size: 7.38 GB (15466496 blocks)
	        Announced size: 30.00 GB (62914560 blocks)
	                Module: 32.00 GB (2^35 Bytes)
	Approximate cache size: 7.00 MB (14336 blocks), need-reset=no
	   Physical block size: 512.00 Byte (2^9 Bytes)

Probe time: 2'25"
 Operation: total time / count = avg time
      Read: 1.42s / 32944 = 43us
     Write: 2'22" / 215152 = 664us
     Reset: 493.5ms / 2 = 246.7ms
dzrmo@bergamont ~/src/f3-6.0 $

Dubious Micro-SD

UPDATE: I found Russian website where this same SD (sip14076k011a) was tested, although using different test software. Anyway, it also failed their tests – JUNK confirmed!

BTW, although the chip id is identical, the Russian website lists the SD (sip14076k011a)  as ADATA microSDHC Class-4 8-Gb. At least the size is basically correct in the ADATA branded card versus my unbranded version.

 

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2 Responses to Dubious eBay SD Cards – Caveat Emptor

  1. Doug Drye says:

    Neat SD tester I will use that… Too bad you can’t trust our Chinese Ebay Vendors.. I’ve had good luck so far… Especially interested in the PINE 64 idea.. Looks like they have a good array of interfaces.. I’ve been thinking about putting a gate up on our driveway at the new house to stop the curious folk from driving up my driveway despite the warning signs.. I will need something to control the camera and gate… This looks perfect..
    Doug

    Like

  2. Never used F3..interesting utility. That being said, anything from Ebay is worth a fake-or-real check these days. Especially the things coming in from China, and other countries. Electronic equipment to car parts, the Chinese definitely know how to make good replicas. May be lacking in function but at least the items look somewhat like the real one :).

    Like

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